Create an eerie entrance. Make your guests pass through a macabre graveyard scene before entering the house. Elsass recommends creating realistic grave markers by using rubbings from real headstones and then transferring them onto florist's foam. A carving knife dipped into hot wax helps makes carving easier, he says. Age the faux monuments by spray-painting them in weathered-stone colors.

Plan your garden for spooky effect. Choose plants such as sunflowers, cosmos, and other tall wildflowers for a spring garden. When Halloween arrives, these plants will leave behind spooky silhouettes and towering shapes to frame your entryway.

Use architectural salvage for ambience. As part of the yard decor, Elsass perches a menacing black crow atop a vintage wood post from a house demolition sale. Draping the post with rumpled cheesecloth gives it a haunted look. Shop craft stores and Halloween shops for feathered, fake birds.

Encourage guest participation. Entrance to Elsass's parties requires more than an invitation. Each partygoer must bring a fully carved and lit pumpkin in order to get in. Scatter jack-o'-lanterns around the "graveyard" to help guide latecomers to the front door.

Boost the "Wow!" factor. Add ambience to every room and a thrill around every corner. Elsass suggests making sure every room, even the powder room, is fully decorated with ghoulish delights. "I open up the entire house for my parties so people can explore," he says.

Look for focal points. Each room should have at least one riveting feature to spark conversation, he advises.

Include outdoor rooms in the fright fest. Elsass even decorates his sun porch, which he has, on occasion, transformed into a mad scientist's laboratory. For an easy, quick touch to turn your abode into a haunted house, "blow a handful of flour over everything to create 'haunted-house dust,'" he says.

Use lighting to enhance the mood. Increase the air of mystery by turning down the lights and adding strobe lighting in strategic gathering spots, such as the dining room. Editor's Tip: If you don't have dimmers, purchase 7-watt bulbs, which give enough light to see but help keep the atmosphere scary.

Protect your treasured possessions. Little hands (and sometimes big ones) find sturdy Halloween toys irresistible, so Elsass recommends planning ahead. If a piece can be handled without damage, place it within reach for guests to enjoy. Store more valuable pieces in a glass case or out of reach. Editor's tip: If you want to start your own collection of Halloween memorabilia, vintage items can be found online, at flea markets, and at garage sales. Reproductions and newer examples can be found at retailers and online. Watch for sales in the weeks following October 31st as stores move out unsold merchandise to make way for Thanksgiving and Christmas gifts.